<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    *{
      margin: 0;
    }
    header{
      background: rgb(68,68,68);
      width: 100%;
    }
    .nav-inner{
      padding: .3125rem;
      width: 90%;
      margin: auto;
    }
  </style>
</head>
<body>

  <header>
    <div class="nav-inner">

    </div>
  </header>

  <section>

  </section>

  <footer>

  </footer>

  <script>

  </script>
</body>
</html>